The Problems With Using Colour; Colour Management Systems - Oki OKIPAGE 8c Colour Manual

The problems with using colour

As already explained, a computer monitor, where an image is
first viewed, and a printer which produces the final document
use different methods to generate colours. Indeed they are based
around a different set of primaries (RGB for monitors, CMYK
for printers). Monitors do not generate a full range of perfect
colours and neither do printers. There is a limit on how many
colours a monitor or printer can generate. This is known as a
device's colour gamut. Some colours can be reproduced by
both devices, while others can be displayed on a monitor but
cannot be printed or vice versa. This in practice may lead to a
colour print not resembling the original on-screen image. So
what has happened?
Images (graphics and text) can be captured through scans or
digital photography, or input directly into the PC via
applications programs. However the original image is
obtained, it will be displayed and manipulated in RGB colour
space (on-screen) and finally converted to CMYK for print.
Each of these processes requires data conversion/
manipulation. An image seen on a computer monitor relies on
the monitor's ability to reproduce the image and represent
colours within it. Adjustments such as brightness, colour and
contrast also tailor the image to the preference of the viewer
rather than a display of true colour. The data sent to the printer
may not be adjusted to allow for imperfections in the inks used.
Colour Guide

Colour management systems

Colour Management Systems (CMS) such as those found in
the OKIPAGE 8c printer driver, allow for any mismatches that
may occur between the RGB and CMYK conversion process.
Colour matching systems go a long way to ensuring a better
match between the input data and printed result but cannot
always allow for monitor adjustment or a variation in paper
stock. Paper can sometimes appear blue or cream in hue which
will have an effect on the light reflected from the page and
therefore change the appearance of some colours. The texture
of the paper used will affect the way that light is scattered and
may also result in patches of light or dense colour. It is therefore
best to find and adopt a paper that provides you with the best
results. This of course may be a process of trial and error, but
some recommendations are given in the User's Guide.
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